Modern-day automotive engines, as is generally well known, are subject to engine knocking or pinging due to pre-ignition at low revolution rates for heavy loads due to a problem in the fuel burning rate. That is, most grades of gasoline have a burning rate which is optimized for cruising speeds corresponding to generally high engine revolution rates. The rate of burning, in regular grades of gasoline, is controlled by the addition of tetraethyl lead. For "no-lead" grades of gasoline, an additive such as octane is employed. The amount added is usually a compromise between good power and low revolution rates and good fuel economy at cruise speeds. It is generally not possible to produce a gasoline which has the correct burning rate for both.
It is accordingly an object of the present invention to provide a device to be used with an automotive engine which injects a fuel additive into the engine which controls the rate of fuel burning over the entire sprectrum of engine speeds so as to maximize engine power without knocking at low speeds while maintaining very good fuel economy at higher engine speeds.
Moreover, it is an object of the invention to provide such an injector device which permits the utilization of a low grade of gasoline which has little or no of the costly additives which have heretobefore been necessary.